Nucleus beads rolling inside the pearls?!!!

Hi everybody! I just bought these "blue Japanese akoya pearls" from an EBay seller called "chin's pearl", for 20 USD and around $4 shipping. I received them today and I think I just got myself faux pearls, but very interesting ones. So they actually look like the photos on eBay, good luster actually, and I was quite pleased until I hold them in my hand. They are really, really light. The weirdest part is I can hear the "rolling" sound from inside. They are actually gritty, and when I rubbed them together there are white powder, and when I wiped them the surface is back to normal. The seller said in the description that the Nucleus are "independent and flexible". Is that really some new nucleus type, or is it just some scrappy lies? In this post I attached the photos of the "pearls" and the ebay page. I kinda want to keep these for educational purposes, but I hope to know what kind of "pearls" these are and hopefully can use that information to get a refund.
I am so sorry for the background and the photo's alignment. I posted this on my phone so I don't know how to rotate them. Also I just found out that behind the window is where I can take the best photos (I think)

Those look like the real deal. FYI I've had issues with the bead nucleus in akoyas come loose from the nacre and roll around on the "inside". I believe others here have also experienced this with south sea pearls.

They look like real pearls but the nucleus being loose and moving around is a downer because it's going to be hard to find the drill hole in the nucleus to set them, if it rotates.

Hopefully P-G members with experience dealing with loose nuclei can give you tips on finding the drill holes.

Don't feel too badly. We have all made buying errors and at least these weren't too costly. They are pretty; you could just park them in a shell and enjoy looking at them, or put them in a small cage and wear as a pendant.

Thank you so much for the replies! I just learned something new today! I'm glad I actually bought what I should get. The pearls are surprisingly light so I was quite concerned. I have a question though. What is it that make pearls' weight so different from each other? I have a few pearls from druzy that feel pretty normal, then a few from pearl society that feel around .5 times heavier and denser, and these pearls that are super light? I have always wondered if I should use pearl's weight and density as ways to identify real pearls, but after this maybe they are not good methods.

It may interest you to know that a small difference in the diameter of 2 pearls makes for a significantly larger difference in volume, and therefore also a difference in weight. (I assume the pearls from the 2 vendors you named were not exactly the same size and shape.)

I have one strand of absolutely gorgeous blue baroque akoya pearls with loose nuclei. Restringing them was a b!tch. But they are real and they are beautiful. I've also restrung my mother's baroque South Sea rope, and some of those pearls had loose nuclei, too. It's a pain when you are trying to string or set the pearls, but they are real pearls.

I have one strand of absolutely gorgeous blue baroque akoya pearls with loose nuclei. Restringing them was a b!tch. But they are real and they are beautiful. I've also restrung my mother's baroque South Sea rope, and some of those pearls had loose nuclei, too. It's a pain when you are trying to string or set the pearls, but they are real pearls.

I concur what BWeaves mentions - I have some BBAs that were drilled and then the nuclei moved around which made most of them unusable for stringing. But I took this as a learning experience to make sure to specify next time that pearls with loose nuclei would not be acceptable. Lesson learned.

The thing is they are half drilled so you might be able to set them. . even if you can't find the original drill hold. See if you can get a thin needle into them. If you can get even 2mm you might be able to use a small dangle with a cap and pin .. something like a small circle bail with a small cap. Between the cap and the pin you could get enough hold to use them as dangles on Threaders. ??

I concur what BWeaves mentions - I have some BBAs that were drilled and then the nuclei moved around which made most of them unusable for stringing. But I took this as a learning experience to make sure to specify next time that pearls with loose nuclei would not be acceptable. Lesson learned.

It's pretty easy to sort out a loose nucleus especially if you have a pearl drill.
1 If you can be bothered squirt some glue into both drill holes and allow to set (wipe off any on the outside obviously).
2 Put the pearl into the drill very carefully aligning the tip of the bit with both holes (if there are two). flip back and forth several times to check. The bit will go through the glue easily if you have used it but the glue will hold the nuke in place
3 re-drill the nucleus from one side only
4 leave the pearl on the drill bit, then carefully ease pearl off the bit and simultaneously onto a scrap of wire to hold it in place (bend wire at 90Deg to secure in place) until threading or setting.
5 do not remove wire until pearl is at least half threaded onto needle/finding because if you do...see 1 and repeat!

I never even knew that nuclei could be loose and roll around inside pearls until I restrung my BBAs.

I also find those particular akoyas to feel "light." I actually wondered if the nuclei were hollow plastic beads because even when I found a hole, it seemed like there wasn't a tunnel through the bead but a big open space, which made it hard to find the hole on the other side, even with a firm needle. On the plus side, they're not heavy to wear. On the minus side, they're almost too light feeling. But since the nuclei are loose I can tell they have VERY thick nacre, so that's good.